[JURIST] Seventeen states Wednesday filed a petition [PDF text; press release] in the US Court of Appeals for the DC Circuit seeking to compel the US Environmental Protection Agency (EPA) [official website] to comply with last year's Supreme Court ruling [text; JURIST report] that the EPA has the authority under the Clean Air Act [text] to regulate the emission of "greenhouse gases" by automobiles. The plaintiffs allege that the EPA has failed to issue any regulations for greenhouse gases and are asking the court to order the agency to take action within 60 days.
During March testimony [statement, PDF] before the Senate Appropriations Committee [official website], EPA Administrator Stephen L. Johnson [official profile] refused to disclose a timeline [JURIST report] for the agency's compliance with the Supreme Court ruling. AP has more.